Conventionally, shapes of granular materials have been measured by taking images of granular materials using existing scanners and processing the taken image via personal computers and the like. Patent Document 1 and Patent Document 2 disclose alignment devices for placing multiple grains in an aligned state on a reading surface of a scanner, wherein the use of the alignment devices enable image of multiple grains to be taken easily and simultaneously.
However, in order to perform a highly accurate measurement in measuring the shapes of granular materials, it is necessary to measure not only the dimensions of the length (X) and the width (Y) but also the thickness (Z) of the materials, as shown in FIG. 12. However, the dimensions of the length and width of the materials could be measured by the conventional methods, but the dimension of the “thickness” could not be measured thereby.
Thus, development of methods for measuring not only the dimensions of the length and width of the granular materials but also the dimension of the “thickness” of the materials had been desired in order to measure the shapes of granular materials using images taken via scanners.